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Diffstat (limited to 'drivers/cpufreq/cpufreq_governor.h')
| -rw-r--r-- | drivers/cpufreq/cpufreq_governor.h | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h new file mode 100644 index 000000000000..f6616540c53d --- /dev/null +++ b/drivers/cpufreq/cpufreq_governor.h @@ -0,0 +1,176 @@ +/* + * drivers/cpufreq/cpufreq_governor.h + * + * Header file for CPUFreq governors common code + * + * Copyright (C) 2001 Russell King + * (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>. + * (C) 2003 Jun Nakajima <jun.nakajima@intel.com> + * (C) 2009 Alexander Clouter <alex@digriz.org.uk> + * (c) 2012 Viresh Kumar <viresh.kumar@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef _CPUFREQ_GOVERNER_H +#define _CPUFREQ_GOVERNER_H + +#include <linux/cpufreq.h> +#include <linux/kobject.h> +#include <linux/mutex.h> +#include <linux/workqueue.h> +#include <linux/sysfs.h> + +/* + * The polling frequency depends on the capability of the processor. Default + * polling frequency is 1000 times the transition latency of the processor. The + * governor will work on any processor with transition latency <= 10mS, using + * appropriate sampling rate. + * + * For CPUs with transition latency > 10mS (mostly drivers with CPUFREQ_ETERNAL) + * this governor will not work. All times here are in uS. + */ +#define MIN_SAMPLING_RATE_RATIO (2) +#define LATENCY_MULTIPLIER (1000) +#define MIN_LATENCY_MULTIPLIER (100) +#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000) + +/* Ondemand Sampling types */ +enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE}; + +/* Macro creating sysfs show routines */ +#define show_one(_gov, file_name, object) \ +static ssize_t show_##file_name \ +(struct kobject *kobj, struct attribute *attr, char *buf) \ +{ \ + return sprintf(buf, "%u\n", _gov##_tuners.object); \ +} + +#define define_get_cpu_dbs_routines(_dbs_info) \ +static struct cpu_dbs_common_info *get_cpu_cdbs(int cpu) \ +{ \ + return &per_cpu(_dbs_info, cpu).cdbs; \ +} \ + \ +static void *get_cpu_dbs_info_s(int cpu) \ +{ \ + return &per_cpu(_dbs_info, cpu); \ +} + +/* + * Abbreviations: + * dbs: used as a shortform for demand based switching It helps to keep variable + * names smaller, simpler + * cdbs: common dbs + * on_*: On-demand governor + * cs_*: Conservative governor + */ + +/* Per cpu structures */ +struct cpu_dbs_common_info { + int cpu; + u64 prev_cpu_idle; + u64 prev_cpu_wall; + u64 prev_cpu_nice; + struct cpufreq_policy *cur_policy; + struct delayed_work work; + /* + * percpu mutex that serializes governor limit change with gov_dbs_timer + * invocation. We do not want gov_dbs_timer to run when user is changing + * the governor or limits. + */ + struct mutex timer_mutex; +}; + +struct od_cpu_dbs_info_s { + struct cpu_dbs_common_info cdbs; + u64 prev_cpu_iowait; + struct cpufreq_frequency_table *freq_table; + unsigned int freq_lo; + unsigned int freq_lo_jiffies; + unsigned int freq_hi_jiffies; + unsigned int rate_mult; + unsigned int sample_type:1; +}; + +struct cs_cpu_dbs_info_s { + struct cpu_dbs_common_info cdbs; + unsigned int down_skip; + unsigned int requested_freq; + unsigned int enable:1; +}; + +/* Governers sysfs tunables */ +struct od_dbs_tuners { + unsigned int ignore_nice; + unsigned int sampling_rate; + unsigned int sampling_down_factor; + unsigned int up_threshold; + unsigned int down_differential; + unsigned int powersave_bias; + unsigned int io_is_busy; +}; + +struct cs_dbs_tuners { + unsigned int ignore_nice; + unsigned int sampling_rate; + unsigned int sampling_down_factor; + unsigned int up_threshold; + unsigned int down_threshold; + unsigned int freq_step; +}; + +/* Per Governer data */ +struct dbs_data { + /* Common across governors */ + #define GOV_ONDEMAND 0 + #define GOV_CONSERVATIVE 1 + int governor; + unsigned int min_sampling_rate; + unsigned int enable; /* number of CPUs using this policy */ + struct attribute_group *attr_group; + void *tuners; + + /* dbs_mutex protects dbs_enable in governor start/stop */ + struct mutex mutex; + + struct cpu_dbs_common_info *(*get_cpu_cdbs)(int cpu); + void *(*get_cpu_dbs_info_s)(int cpu); + void (*gov_dbs_timer)(struct work_struct *work); + void (*gov_check_cpu)(int cpu, unsigned int load); + + /* Governor specific ops, see below */ + void *gov_ops; +}; + +/* Governor specific ops, will be passed to dbs_data->gov_ops */ +struct od_ops { + int (*io_busy)(void); + void (*powersave_bias_init_cpu)(int cpu); + unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy, + unsigned int freq_next, unsigned int relation); + void (*freq_increase)(struct cpufreq_policy *p, unsigned int freq); +}; + +struct cs_ops { + struct notifier_block *notifier_block; +}; + +static inline int delay_for_sampling_rate(unsigned int sampling_rate) +{ + int delay = usecs_to_jiffies(sampling_rate); + + /* We want all CPUs to do sampling nearly on same jiffy */ + if (num_online_cpus() > 1) + delay -= jiffies % delay; + + return delay; +} + +u64 get_cpu_idle_time(unsigned int cpu, u64 *wall); +void dbs_check_cpu(struct dbs_data *dbs_data, int cpu); +int cpufreq_governor_dbs(struct dbs_data *dbs_data, + struct cpufreq_policy *policy, unsigned int event); +#endif /* _CPUFREQ_GOVERNER_H */ |